The present invention relates to intra-uterine contraceptive devices.
None-chemical contraceptive means generally known as diaphragms are known in the prior art. Such diaphragms are normally associated immediately before being used, with spermicide and/or medicinal substances. Generally such diaphragms comprise an outer structure which is a rubber cap peripherally fixed to a base structure. These diaphragms are of circular or oval shape and the outer structure is generally planar. Moreover, the outer structure which is elastic may be peripheraly deformed by a user or a therapist to anatomically adapt its shape.
Known vaginal diaphragms are disclosed, for example in U.S. Pat. Nos. 961,880; 2,087,610; 2,443,943; 2,463,356; 2,529,363; 2,638,896; 2,664,082; 2,679,589; 2,823,669; 3,169,894; 2,875,755; 3,060,931; 4,031,886 and the German Pat. No. 557,914.
The contraceptive diaphragm disclosed in U.S. Pat. No. 2,443,943 to T. Young includes an outer structure formed of two separate steel segments housed in a spiral spring incorporated in a rubber sleeve.
The diaphragm is disclosed in U.S. Pat. No. 2,463,356 to J. T. Clark, in which the oval outer structure is a rubber sleeve accommodating two flat springs each having its ends juxtaposed to the corresponding ends of another spring to provide for an adjustable diaphragm.
The diaphragm disclosed in U.S. Pat. No. 2,823,669 to E. Kunnas is of a circular shape and comprises an outer structure in which two separate steel segments are connected to each other by two small spiral springs, wherein their pointed ends are engaged, all these elements being housed within a larger closed spiral spring which in turn is positioned in a rubber sleeve, so as to provide a diaphragm that may be folded for introduction in the anatomic cavity.
Applicant has suggested a number of model and patent applications concerning, respectively a circular or oval diaphragm in which the cap is connected with the outer structure in accordance with the middle plane of the outer structure, an oval diaphragm in which the inner armour of the outer structure may be extended or shortened in order to modify the dimensions of the diaphragm, a diaphragm whose outer structure comprises a spiral spring incorporating flexible metal bars and is of oval or elliptic cross-section with a main axis substantially parallel to an axis perpendicular to the diaphragm plane.
A pessary disclosed in U.S. Pat. No. 4,031,886 to Morhenn is formed by an outer structure having a specific shape for receiving the human cervix and a bag adapted to receive that outer structure. The bag has two generally planar walls each having four edges and may be impregnated with medicaments.
The inconvenience with known diaphragms, however is that they should be used in association with spermicide and/or medicinal substances to be applied before use and require the availability of a diaphragm and of a container for those substances, which involves practical, psychological and financial problems.
Furthermore, the handling of a gummy material which becomes slimy due to the applied substancies is also inconvenient.
Moreover, the staying of one of such substances on a rubber cap may be uncertain and a source of unpleasant surprises.
In the pessary disclosed in U.S. Pat. No. 4,031,886 the outer structure must be oriented in a unique way in order to be introduced into the bag; the pessary must be applied into the anatonic cavity in a unique direction; the shape of the outer structure can be only adapted to work as a pessary and the outer structure does not allow for adjustments to the shape and dimensions--all the above cause difficulties in use of the disclosed pessary.